Conventionally, in a sequencer unit used for such a system as a factory automation (FA) device, a plurality of sequencers are arrayed and fixed. Such a sequencer includes a terminal block on which a plurality of terminal connection portions, to which wires for input and output of signals are connected, are arrayed. If the wires connected to the terminal connection portions are not held together and are left as they are, the wires may interfere with an adjacent sequencer, thus making attachment and detachment of the sequencer difficult. Furthermore, the visibility of the wiring state is likely to decrease, thereby delaying detection of dropout or the like in the wiring and making it difficult to prevent a ground fault or the like.
Therefore, the wires connected to the terminal connection portions are generally banded and held together with a banding band. To further prevent the wires from spreading apart, the banding band for holding the wires together is fixed. For example, in Patent Literature 1, a band attachment portion for fixing a banding band to a terminal block is provided.